Alaskan Rivers

The rivers of Alaska run very cold due to general climate and the influence of glaciers on the water content. The Tanana, Delta, Nenana, Copper, and Susitna are heavily influenced by silt that is borne into the river by glacial melt. These five rivers run a light brown and are not clear during the summer. The fish use these rivers as highways to their spawning grounds in clear tributaries. The Alaska Range, Wrangell Mountains, and Brooks Range retain their snow year-round in the upper elevations, which means they're always supplying ice-cold water to the big rivers and small streams in their watersheds. Shallow rivers freeze to the bottom, forcing fish to move to larger, deeper rivers over the long winter. Salmon species are not affected because they spawn and die. Grayling, whitefish, pike, and burbot must live in a state of hibernation for almost six months. Sometimes the oxygen levels get dangerously low, causing excessive winter kill. Late spring and early summer result in new growth, new insects, and new life for all survivors. Like all rivers worldwide, Alaska's rivers are subject to increased and decreased flow and depth according to rainfall, snowfall, and snow/glacier melt. A river at low to medium levels can overrun its banks and become unfishable due to rainfall or warm weather that accelerates the melting of snowpack and glacier. It's a tough life for an Interior Alaskan fish, but they find a way to get to the endless days of summer!

Alaskan Lakes

The lakes of Alaska develop great depths of ice in the fall and winter. Ice 3-5 feet deep is common for a lake in mid-winter. Many of central Alaskan lakes are stocked with fish because natural populations have a hard time surviving in the poorly oxygenated water. Lakes that have natural populations of lake trout, whitefish, and grayling are very deep and rich enough in food and oxygen to sustain life during the winter. Alaska has no lack of water; the state has over 3,000,000 lakes. The richest lakes are near the ocean and feature massive runs of all five species of salmon. Many other species of fish follow the salmon on their spawning runs in an effort to eat their eggs and rotting remains. Some lakes in Interior Alaska are tea-colored. Some are crystal clear, and some are slightly silty. Sometimes fish may be in a lake on a seasonal basis. The vegetation in Interior Alaska lakes must regrow to its summer splendor after a dark and cold winter. The insect activity multiplies greatly around this new plant growth. Lakes are filled with nymphs of mosquitos, damselflies, caddis, and hundreds of other insects. It's best to check with ADFG or the locals to find out if a lake holds fish. Alaskan lakes can be a mystery, but it's a certainty won't find any bluegills or large-mouth bass!

This page was last modified on November 22, 2004

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